Six flight modes can be done without tying up two radio channels.

A tip for getting 6 flight modes without using up 2 radio channels on your radio.

On some radios (eg JR X2720 7-channel) you can mix the 3-position flap channel
with itself, rather than mixing with gear or aux which would prevent you from
using the gear or aux radio channel for something else. The mixing switch isn't itself a
radio channel so by careful setup of the mixing offset and percentages it’s
possible to get the six positions required just using the one radio channel
(the flap channel) and the mixing switch.

To find whether you can do this on your radio, you just need to check whether it can mix flap with flap, and if so then it should be possible. Start by setting the flap positions with mixing off, for modes 0, 2 and 4, and then with mixing on for modes 1, 3 and 5. 

I posted detailed instructions for doing this on a JR X2720 as a comment on this page:

but the webmaster asked for the info to be posted here so it could be linked to, so here it is:


Here is a guide for setting up 6 flight modes on a JR Propo X2720 seven
channel radio. I have achieved this while only using one of the active channel
inputs (the flap channel) leaving gear and aux free for other purposes. The
flap switch on the right shoulder is 3-position and the mixing switch on the
left shoulder provides the cut over to the other three modes. By setting the
mix function to FLAP -> FLAP it can be done without losing the aux or gear

Here are the settings: In the Function select mode, go to Program Mix 1
Set it to FLAP -> FLAP +rate=100% -rate=-50% offset = +10 SW = MIX

In the Function select mode, go to FLAP System Set FLAP Norm = UP 46%
FLAP Mid = DN 8% FLAP Land = DN 100% ELEV Norm = 0 ELEV Mid = 0 ELEV Land = 0
Auto Land Inhibit

In the System Select Mode, go to Input Select Set D/R switch to Com Aile
(Aileron dual rate switch does all 3 dual rates, leaving mixing switch free)
Set Aux 2 switch to Aux2, Trim inhibit Set FLAP to System, Trim Inhibit

This will give you six positions for pulse widths corresponding to six
flight modes. With the Mix switch off (backwards) you get flight modes 0,2,4 on
the flap switch, and with the mix switch on (forwards) you get flight modes

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Hi, tried this on my JR DX9, with a few minor tweeks managed to get it working :)

First in Function List Mode

Prog mix 1 option

Set flap -> flap

sw select to mix

thro stick inh

exp off

set point 0 to -50

and left everything else alone

Flap system option

set auto land inh

flap norm to u46%

flap mid to u3%

flap land d61%

now in System Mode

DeviceSEL option

couldn't find d/r switch to com aile so ignored this

under flap, trim on, out sys

Thats it.

Back to Mission Planner I'm now getting...

mix pos 1, flpa pos 1, pwm 1322, flight mode 2

mix pos 1, flap pos 2, pwm 1499, flight mode 4

mix pos 1, flap pos 3, pwm 1744, flight mode 5

mix pos 2, flap pos 1, pwm 1140, flight mode 1

mix pos 2, flap pos 2, pwm 1480, flight mode 3

mix pos 2, flap pos 3, pwm 1864, flight mode 6

A simple solution for those who have a transmitter with one or more Gyro channels : Use a gyro channel for APM mode control.

Then simply use flight mode conditions on your transmitter to program a different gyro channel gain for each transmitter flight mode.

Using two or more switches, you can switch flight modes. I'm using 4 switches.

Simple, no mixing, only one channel, and you can even organize your modes priority changing the flight mode conditions order. More you have each mode name printed on the transmitter LCD screen :) That's very nice if you did forget wich button is wich mode !

Another advantage is that you can change transmitter parameters at the same time as you change flight modes (dual rates, throttle curve...).

Cool Tip! Will try this with my JR9303. Thanks, Harry!

I was able to get 6 flight modes on my DX7s using only Flaps radio channel and the Ele D/R switch with the following settings:

AX1 > AX1

Rate:   -33%


Offset: -34%

Trim: Inh

SW: Ele D/R

I have the same. Haven't tried yet but it should work.

I have a JR X9503. I tried it the way Harry suggested and it sort of worked. Some of the positions were off a little so I only got 4 or maybe 5 modes. Actually because of the position of the switches, I would prefer to use matt's technique since the Elev/DR is just to the left of the flap switch.

But my radio is not a DX7 and I'm not having luck finding the various options. This is what I've located:

DeviceSEL - I know I need to set something here but which column? Do I use the FLAP column and how would I set it?

D/R & EXP - Here I have Pos-0 and Pos-1. It looks like I just need to adjust this until I get it right or does someone know the settings?

Flap Sys - Here I set the FLAP to U46, U3, D61 but probably not necessary since I want to use the D/R switch instead of mix switch. Or do I need to change something here also?

Thanks for the help!


I found the APM channel range settings seemed to shift slightly with 2.5 (I set it up originally with an earlier release) so the flap settings just need tweeking, found the easiest way to do this was with it all hooked up and monitoring via the controller config screen as I tweeked the controller. It would be good if they adjusted the planner software to let you adjust the setting ranges on the board manually, guess you can do this directly in the code but so far I've found it easier to use the planner update function rather than doing it manually.

Do you know how to do it like matt schoenholz suggested using the elevator D/R? I think there is a difference in how they labeled things on the DX7 and my JRx9503.

This should be possible but one place I'm getting stuck is in the menu that you get to wen you hold ENT and turn on Tx. There you have the DeviceSEL menu and in there you have:

FLAP which gives you 4 choices for combining. (AUX3 LV, FLAP LV, AUX2 SW, FLAP SW)

I think none of those is what I need. I need EVEL D/R but it doesn't exist in the FLAP choices. It only exists on the GEAR and AUX4 channels but those are just two position channels so doesn't help.

Anyone have a clue on how this can work or maybe it will only work with the mixer switch?

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